Focus Fire

FOCUS FIRE

Focus fire is one of the most important AI concepts to improve your ship. Because battles are won through doing hull damage and hull damage can’t be done until a room’s HP is destroyed (except pen missiles), the quickest way to do a lot of hull damage is to target one room for the entire battle. How do we do that? All you have to do is pick a condition for your targeting command that is only true once in the battle, so that the AI will never retarget. 

The simplest example is to use either of the conditions “enemy ship has full shield” or “Your ship has full shield”. The assumption is that your shield will be full only at the start of the battle and never again, so your weapons will pick a target and then shoot it forever. 

Attach this basic AI to all your lasers, missiles, and hangar and it will carry you to epic league: 

1) None, increase power by one 
2) Enemy ship has full shield, target enemy teleport 
3) Enemy ship has full shield, target enemy shield room

“Enemy ship’s shield” or “your ship’s shield” condition?

Which is better, using “enemy ship has full shield” or “your ship has full shield” as the condition? There are positives and negatives to both. The downside of using “your ship” is that it doesn’t function when the opponent uses the pen spam strategy, because they will never damage your shield. When fighting a pen spammer, you really need to focus fire on one room because these ships are well-equipped to defend and spreading your shots out will equal a loss. The downside of using “enemy ship” is that it doesn’t function when the enemy has no shield, which is typically when their shield is upgrading. Your guns will load but won’t fire as no target would have been defined (all targeting conditions are false).
In either case, if you’re on offense you can manually target your weapons to keep them firing at one room. In summary, “your ship” doesn’t work against pen spam, and “enemy ship” doesn’t work against upgrading shields. I prefer “enemy ship” since the enemy having an upgrading shield is more rare then pen spam, and easier to work around.

Delayed focus fire 

In some cases, a delayed focus fire is desired. What if you want to shoot one room for one phase of the battle, and then switch to another room? There are a few ship HP condition that allow you to do this. 

1) None, increase power by one 
2) Enemy ship has full HP, target enemy hangar
3) None, target enemy shield 

This will shoot the hangar until it’s dead, and then switch to the enemy shield. Note that if the opponent has both a SHL and a SB, it will shoot both of them which isn’t really what we want. If you use this AI, you generally need to select a room type for the second phase that the opponent can have only one of. Or, you can be OK with shooting both of them, like AA for example.

Other focus-fire AI’s

There are other options for implementing a focus fire AI. Let’s consider some basic AI and build up to them.

1) None, increase power by one 
2) None, target enemy shield
3) None, target enemy laser

All your weapons will start shooting at the enemy shield, due to line 2. However, once destroyed, the shield room isn’t considered a potential target. The AI will therefore move on to line 3, and start shooting at a laser. Once that first laser is destroyed, it will cease to be a valid target like the shield. The action “target enemy laser” will pick a new laser that isn’t destroyed. If the shield is repaired, the AI will switch back to it. And then move to lasers again. Hull damage will only be possible once ALL the shield(s) and lasers have been destroyed, which will take quite a long time if the enemy has any repairers.

Full Shield conditions as described above avoid this issue, due to the fact they’re typically valid only for a couple seconds at the start of battle. Afterward, no targeting line will be valid, and in the absence of a new target, weapons just keep shooting their last target.

There are two other ways that will allow us to continue shooting at a destroyed room. The first uses the Python3 action “Continue Current Job”, which maintains the current target. In the following AI, your weapons will pick a shield to shoot at the start of the battle, or a laser if the enemy has no shield rooms. As soon as that first target is destroyed, the second line will prevent the execution of the lines below it, and therefore maintain focus on the room.

1) None, increase power by one 
2) Target Room destroyed, Continue Current Job
3) None, target enemy shield
4) None, target enemy laser 

Without Python3 there is one last way to focus fire, shown below:

1) None, increase power by one 
2) Enemy room HP < 50%, target condition room
3) None, target enemy shield
4) None, target enemy laser 

Again, the AI will start shooting at the first valid target using lines 3 and 4. Once that room is damaged below 50%, line 2 will continue to target that room even if it gets fully destroyed, therefore keeping our focus. The only potential issue is if you use boarders or other weapons that destroy rooms other than those listed on you main weapons. If this is the case, weapons with the AI above will switch to target destroyed room if the room they’re currently focusing is repaired. This occurs even if that destroyed room isn’t a room type in line 3 or 4. If you use roaming boarders, you probably want to shoot at any destroyed room to get in hull damage, but if you use camping boarders you will likely shoot at your own crew sitting in a destroyed room.

Overall, if you want permanent focus on one room, the PY3 method is preferable. If you don’t have PY3 researched yet, the “full shield” condition AI will work well. Lastly, if you don’t use camping boarders and have the same weapon AI on all weapons, targeting rooms with <50% health is just as effective as the PY3 method.

How do I know what to shoot at?  

The short answer is that focus firing the opponent’s ship damages or incapacitates whatever room you are focusing. So what room makes you lose the most? Shoot that one. Have your focus fire AI list the rooms you want to shoot, with the most deadly to you and the least deadly on bottom. Just include enough room types to guarantee that the enemy will have at least one of them on their ship, so that at least one command is valid. 

Aggressive focus fire 

The longer answer is that your focus fire AI should be strategy dependent. If you are an aggressive build with BT’s, then you want to end the battle as fast as possible and should be targeting the rooms that are the weakest. Look at ships you face, and pick the least armored targets you can find. A typical aggressive AI would be:

1) None, increase power by one 
2) Enemy ship has full shield, target enemy med bay
3) Enemy ship has full shield, target enemy droid room 
4) Enemy ship has full shield, target enemy laser
5) Enemy ship has full shield, target enemy missile 

You can see that these are all low health rooms, and the top two are 2×2 rooms that are hard to armor. You’ll be able to push through a lot of hull damage quickly by focusing them. The opponent’s ship generally has a lot of lasers, and sometimes your AI will pick you with a lot of armor. If you can find one room that is unarmored or has just one or two armor, manually retarget to focus that room. And don’t put underarmored rooms on your ship!

Defensive focus fire 

On the other hand, if you are a defensive build, you can be more strategic about eliminating key threats, knowing that you will win the long game. You’ll want to shoot rooms that cause you to lose, even if they are highly armored. A more defensive/balanced focus AI would be: 

1) None, increase power by one 
2) Enemy ship has full shield, target enemy teleport 
3) Enemy ship has full shield, target enemy hangar (if you’re not running AA on your ship)
4) Enemy ship has full shield, target enemy shield 

You can see these rooms have more health, and will generally be better armored than the rooms in the aggressive AI. However, they also have a bigger impact on the battle and investing the damage to destroy them is worth it over the longer battle. An aggressive ship doesn’t care that the opponent’s shield is able to recharge four or five times in a short battle, they’ll punch through it; a defensive ship wants to stop the enemy shield from recharging ten or twelve times in a long battle, because that’s another 50% ship health the opponent will gain. 

The answer is never reactors 

Please, please, don’t shoot reactors. It seems like a good idea at first glance, because reactors are critical to the operation of a ship and everyone has them. However due to their high health (7 for the small reactors), it’s super easy for a repair crew to repair them so you stop doing hull damage. Let’s take a simple example, where you have a mystical 3 DPS. Your choices are to shoot either the enemy android studio, which is highly armored and has 50% damage reduction from armor; or shoot a reactor, which is armored lightly for just a 20% damage reduction. So every second, if you’re shooting the AS you are doing 1.5 damage to the AS if it’s alive and to the hull if it’s not. If you’re shooting the reactor, you are doing 2.4 damage to the reactor if it’s alive and to the hull if not. 

I’ll also assume that 3 seconds after a room takes damage, crew come in and fully repair the room. This is fairly realistic, since two crew can easily repair an AS with one repair action each, and three crew can repair a reactor. The three seconds represents the time it takes the repair crew to run to the room.

The reactor kill takes 25% longer in my example. The core reasons for this hold up in game: 

• Reactors have so much health that they soak up a lot of DPS, even when sparsely armored. 
• Repair is very fast compared to the DPS of guns. Look at the weapon DPS chart – a completely maxed level 11 ship with two MLZ, two PLA, LB, MG and ION only does 1.897 DPS. Since even 3* crew generally have repair of 2+/second, one crew can repair a room while it’s being shot. 
• Your main damage to hull comes when a crew is moving to repair the room. Because reactors have high health, the opponent’s crew has warning when the room starts to get damaged and has more time to reach the room and repair it. (You also do damage while the room is on fire, because crew can’t repair a burning room. This case is still the same, since the crew has more time to put out the fire.)

seconds	AS health	Hull health	Reactor health	Hull health
0	3	12	7	12
1	1.5	12	4.6	12
2	0	12	2.2	12
3	0	10.5	0	11.8
4	3	9	7	9.4
5	1.5	9	4.6	9.4
6	0	9	2.2	9.4
7	0	7.5	0	9.2
8	3	6	7	6.8
9	1.5	6	4.6	6.8
10	0	6	2.2	6.8
11	0	4.5	0	6.6
12	3	3	7	4.2
13	1.5	3	4.6	4.2
14	0	3	2.2	4.2
15	0	1.5	0	4
16		Dead	7	1.6
17			4.6	1.6
18			2.2	1.6
19			0	1.4
20				Dead